Within the past decade there has been an increased awareness of the impact that carbon dioxide and methane emissions have on the earth's environment, and society has responded to the resultant global warming threat by adopting, where possible, clean energy generation practices and policies. In addition to a focus on renewable energy production, we have taken steps to curb excessive use of our fossil fuel energy resources. Consumers have engaged in energy efficiency and demand response programs so as to maximize the resources that are available to us.
Along with the shift in consumer sentiment (concerning the source of and use of electric energy), consumers have come to accept electric vehicles (EVs) as a realistic alternative to vehicles that are propelled by fossil fuels. Electric vehicles can function on the use of renewable energy, and they substantially reduce harmful exhaust pollutants that are emitted into the atmosphere.
One of the more salient concerns of potential EV owners is the phenomena known as “range anxiety”. EVs are currently capable of traveling up to 300 miles on a full charge, but the time required to acquire a full recharge is a major concern (which may be several hours), as is the availability of appropriate charging equipment. The “range anxiety” of EV owners may be described as the concern of being stranded—if not indefinitely, then at least for several hours.
Still, for those drivers that tend to travel less than 200 miles on a given day and have a several hour period subsequent to traveling where the EV can be recharged, the EV can be a practical mode of transportation. However, for those instances where the EV owner may need to travel beyond a safe zone, a more wide-spread EV charging network may be necessary for the EV to appeal to the masses.
In addition to the need for a wide-spread charging network, the charging infrastructure equipment itself must be capable of engaging with the subject EV. Presently there are a variety of different charging connectors that are being utilized for a variety of differing EV platforms. The following Table 1 presents a non-exhaustive listing of available charging connectors and the respective applicable standards:
TABLE 1Manufacturer Pin Configuration StandardYazaki SAE J1772 AC CHADEMO AC (Japan has unique control signals and overall physical shape) CHADEMO JEVS G105-1993 (DC) Fujikura SAE J1772 AC CHADEMO AC (Japan has unique control signals and overall physical shape) CHADEMO JEVS G105-1993 (DC) Japan Aviation Electronics Industry CHADEMO AC (Japan has unique control signals and overall physical shape) CHADEMO JEVS G105-1993 (DC) Sumitomo Electric Industries CHADEMO AC (Japan has unique control signals and overall physical shape) DYDEN CHADEMO JEVS G105-1993 (DC) FURUKAWA ELECTRIC CO., LTD CHADEMO AC (Japan has unique control signals and overall physical shape) CHADEMO JEVS G105-1993 (DC) Eaton Corporation SAE J1772 AC AeroVironment SAE J1772 AC Fujikura Ltd. CHADEMO AC (Japan has unique control signals and overall physical shape) CHADEMO JEVS G105-1993 (DC) Coulomb Technologies SAE J1772 AC Tesla Motors Tesla Supercharger proprietary
The CHAdeMO standard provides the most comprehensive pin configuration and addresses both alternating current (AC) and direct current (DC) charging.
Each of the above identified charging connectors requires not only direct human interaction, but also the exertion of force in order for the connector and the receptacle to correctly couple.
In late 2011, Japan Aviation Electronics Industry, Ltd. (JAEIL) introduced a then new design for a quick vehicle charger touted as “Intuitive with Easy Operability”. The product messaging further described as the charger as requiring “No need for complex lever manipulation like the other existing chargers, and achieves one-hand operation. Connection to the EV is made by pushing connector into the EV inlet, and is removed by pushing the release button and then pulling the connector, allowing easy operation just like a normal speed charger”.
The new JAEIL charging connector, while attempting to address an ease-of-use issue, continues to require a level of dexterity and strength that may not be available for certain elderly or handicapped persons that are otherwise capable of operating motor vehicles.
The aforementioned charge connectors, all incorporating performance challenges by virtue of the difficulties associated with the exertion required for connector and receptacle mating, have been granted certain intellectual property protections including Nee (U.S. Pat. No. 5,272,431); Hoffman (U.S. Pat. No. 5,344,331); Konda (U.S. Pat. No. 5,593,320); Konda (U.S. Pat. No. 5,807,129 providing a locking device related to the charging connector); Neblett (U.S. Pat. No. 6,371,768) and Yeon (U.S. Pat. No. 8,123,535); as well as pending applications: Williams (Appl # 20020081486); Ohtomo (Appl #20090079389); Fujitake (Appl # 201000228413); Sakurai (Appl # 20100315040); Matsumoto (Appl # 20110034053); Kurumizawa (Appl # 20110201223); Xiaofeng (Appl # 20110260684); Ichikawa (Appl # 20110300753); Ichikawa (Appl # 20120091958); Hani (Appl # 20120091961); Masuda (Appl # 20120098490); Tormey (Appl # 20120135626); Ishida (Appl # 20120186309 providing a locking device related to the charging connector); Osawa (Appl # 20120238131); Osawa (Appl #20120258635); Ichio (Appl # 20120295460); Glick (Appl # 20130017739); Pusch (Appl # 20130049972); Musk (Appl # 20130078839); Hara (Appl # 20130088032); Martin (Appl # 20130089999); Hara (Appl # 20130095678); Umeda (Appl # 20130134937); Kawasaki (Appl # 20130181675); Ishii (Appl # 20130157501); Hara (Appl # 20130196522); Sasaki (Appl # 20130224969) and Ang (Appl # 20130314034).
In addition, attempts have been made to apply robotic technologies to aid in the automation of EV charging, in part offering an added benefit of assisting physically impaired individuals to engage the charging connector with a receptacle. Intellectual property protections have been granted to: Hoffman (U.S. Pat. No. 5,306,999); Lara (U.S. Pat. No. 5,461,298); Wilson (U.S. Pat. No. 5,646,500); Hayashi (U.S. Pat. No. 6,157,162) and Hollar (U.S. Pat. No. 7,999,506), while several additional applicants are pursuing variants of an automated or robotic charging system, including Haddad (Appl # 20110254504); Cornish (Appl # 20120233062); Bonny (Appl # 20120286730); and Gao (Appl # 20130076902). While each of the aforementioned intellectual property and applications involves the application of robotics in some manner, none include an end effector of the type described by this invention that allows those devices to achieve connection without the exertion of significant force and/or without significant end effector manipulation (thus requiring additional functionality of the robotics in terms of robustness and dexterity).
The CHAdeMO standard has been identified as having the most breadth in terms of contact points (including alternating current and direct current energy contacts or poles, control lines and CAN BUS contactors) and, therefore, serves as the standard for the development of this invention. However, the teachings of this invention may accommodate other standards, such as the SAE J1772 configurations, by engaging with fewer contacts on the invention than are available.
The invention disclosed with this application provides a method to align and couple a Connector and a Receptacle which minimizes the necessity for exertion of manual mechanical force (whether by person or by automated equipment). Furthermore, the invention facilitates a truly universal approach to EV charging as the Connector, through myriad available adapters, allows for currently existing charging equipment to become retrofitted and thereby function with the charging Unit that is the subject of this application.